michael/pathfinder
michael
/
pathfinder
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Allow construction of a `Transform3DF32` from a quaternion describing a 

rotation.

Closes #111.
This commit is contained in:
Patrick Walton 2019-03-20 16:26:43 -07:00
parent a0aeb124ad
commit 26fea26f87
1 changed files with 17 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
geometry/src/basic/transform3d.rs
View File

@ -97,6 +97,23 @@ impl Transform3DF32 {
0.0, 0.0, 0.0, 1.0) 0.0, 0.0, 0.0, 1.0)
} }
/// Creates a rotation matrix from the given quaternion.
///
/// The quaternion is expected to be packed into a SIMD type (x, y, z, w) corresponding to
/// x + yi + zj + wk.
pub fn from_rotation_quaternion(q: F32x4) -> Transform3DF32 {
// TODO(pcwalton): Optimize better with more shuffles.
let (mut sq, mut w, mut xy_xz_yz) = (q * q, q.wwww() * q, q.xxyy() * q.yzzy());
sq += sq; w += w; xy_xz_yz += xy_xz_yz;
let diag = F32x4::splat(1.0) - (sq.yxxy() + sq.zzyy());
let (wx2, wy2, wz2) = (w.x(), w.y(), w.z());
let (xy2, xz2, yz2) = (xy_xz_yz.x(), xy_xz_yz.y(), xy_xz_yz.z());
Transform3DF32::row_major(diag.x(), xy2 - wz2, xz2 + wy2, 0.0,
xy2 + wz2, diag.y(), yz2 - wx2, 0.0,
xz2 - wy2, yz2 + wx2, diag.z(), 0.0,
0.0, 0.0, 0.0, 1.0)
}
/// Just like `glOrtho()`. /// Just like `glOrtho()`.
#[inline] #[inline]
pub fn from_ortho(left: f32, right: f32, bottom: f32, top: f32, near_val: f32, far_val: f32) pub fn from_ortho(left: f32, right: f32, bottom: f32, top: f32, near_val: f32, far_val: f32)